What are some alternatives?
When comparing Hipster Sound and Defonic, you can also consider the following products
Noisli - Noisli is a fantastic background noise and color generator for working and relaxing. Online soothing ambient sounds like White noise, Rain and Coffee Shop.
Noizio - Feeling that the noise of the big city is too much for you to bear?
Studiowave - Chillout tunes and inspiration
Krisp - Mute the background noise during your calls
A Soft Murmur - Ambient sounds to wash away distraction.
GitHub Audio - Tracks events across GitHub to generate calming work music